Telecommunications users frequently receive multiple services such as voice, video, and data from a single provider. Often, the services are combined for delivery over a single physical layer such as twisted pair, coaxial cable, or fiber. As voice and video service has traditionally been provided through a dedicated connection, subscribers expect reliable service and can be intolerant of even minor disruptions such as dropped calls or loss of picture. However, as services such as voice-over-Internet Protocol (VoIP) or Internet Protocol Television (IPTV) are combined with data service, a single point of failure is introduced for the combined services and heavy use of the data service can impact the quality of the voice and video services.
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